Nails form from molten iron. what type of change is this and why?

Which of the following statements is true? a. the main cause for speciation is an increase in gene flow. b. organisms that reproduce asexually are not considered part of a species. c. on a tree of life diagram, speciation is shown by the merging of two different lineages. d.the size of the geographic area inhabited by a population can cause speciation.

I’m stuck on this question cuz i’m stupid sksksksk

What environmental cues and landmarks do the geese use to determine the timing and direction of their migration over the mountains? how do they find their way?